As the Russian military's invasion reached the outskirts of Kyiv, he said the world is continuing to observe what is going on in Ukraine from afar.

He said missile strikes had resumed at 4am but Russian troops had been stopped from advancing in most directions.

Earlier he ordered a mass mobilisation decree which paves the way for civilians to take up arms against Vladimir Putin's forces as Russian troops embarked on the biggest attack by one country on another in Europe since the Second World War.

Key developments:
• Russian forces seize former Chernobyl nuclear power station
• Kyiv "could well be under siege" - Blinken
• PM unleashes UK's 'largest set of sanctions ever' on Russia
• US sanctions announced as 7,000 troops head to Germany
• Ukrainian president: Russian attack 'like fascist Germany in WWII'
• Champions League final set to be moved from Russia

The Ukrainian army is defending positions on four fronts despite being outnumbered, the deputy defence minister said.

In a video address in the early hours of Friday, Mr Zelenskyy - who remains in Kyiv - announced 137 Ukrainians had been killed so far and 316 injured.

"According to our information, the enemy has listed me as target number one, and my family - as target number two. They want to destroy the country politically, terminating the head of state," he said.

Kyiv hit by 'horrific rocket strikes' as Russian invasion enters second day - live updates

Mr Zelenskyy's mobilisation order covers regions nationwide, including Kyiv, where several explosions have been heard after missile strikes resumed.

Ukraine's foreign minister Dmytro Kuleba said the city had been struck by "horrific Russian rocket strikes", while US Secretary of State Antony Blinken warned it "could well be under siege".

Photos posted by the emergency services showed a damaged residential building.

Kyiv's mayor, former heavyweight champion boxer Vitali Klitschko, tweeted that three people were injured, with one of them in a critical condition.

A Ukrainian government adviser said Russia plans to use tanks to break through to the capital and Ukrainian forces are ready to respond with anti-tank missiles supplied by foreign allies.

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Zelenskyy's call to arms as invasion continues

Klitschko, 50, who's been mayor since 2014, is among those set to answer the president's mobilisation decree, telling ITV he had "no other choice but to take up arms" and that Mr Putin had "totally" lost his sense of reality.

His brother, Wladimir Klitschko, will also enlist.

Lasting 90 days, it means all conscripts and reservists will be expected to help "ensure the needs" of Ukraine's military, as they battle against a "full-scale" Russian assault that has drawn condemnation from around the world.

Some 100,000 Ukrainians are believed to have fled their homes, according to the United Nations, but the country's border guard service has said that males aged 18-60 are not allowed to leave.

It comes after Mr Zelenskyy imposed martial law, putting the military in control of the country.

Ukraine's armed forces believe more than 60 Russian battalion tactical groups - the equivalent of between 30,000 and 60,000 troops - have been deployed.

Mr Putin is thought to be targeting a blockade of Kyiv and the creation of a land corridor on Ukraine's southeastern coast towards the Crimean Peninsula - which Moscow annexed in 2014 - and the Transdniestria region of next door Moldova that is held by pro-Russian separatists.

Later on Friday, the United Nations Security Council will vote on a resolution condemning Russia for its actions in Ukraine and calling for its immediate withdrawal.

It is doomed to fail, given Russia's veto power on the council. However, a diplomatic source in New York - where the negotiations have taken place - told Sky's Mark Stone it was "another chance to isolate Russia".

There will be particular interest in how China votes, given Beijing's foreign ministry refused to accept the reality that Russia had "invaded" Ukraine. It has instead blamed the US for "hyping up" the situation.

What's happening on the ground

With Russia having seized control of Chernobyl, near Pripyat, around 60 miles from Kyiv, attention is now turning to other sites.

One which has been the scene of intense combat so far is Hostomel military airport, which is also near Kyiv. It could prove vital, as Russia could use it to bring more troops into the country.

Elsewhere, fierce fighting has taken place in Sumy and Kharkiv in the northeast, Kherson and Odessa in the south.

Border units, border patrols and checkpoints have been targeted with artillery, heavy equipment and small arms fire, including a missile strike at a border post in the Zaporizhzhya region, officials said.

Before the scenes in Kyiv this morning, the defence ministry in Moscow insisted it was not targeting cities, but using precision weapons, claiming that "there is no threat to the civilian population".

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A US official said Russian forces were moving on three fronts - from annexed Crimea to Kherson in the south, from Belarus - north of Ukraine - towards Kyiv, and from the northeast to Kharkiv.

The official said as part of the "first phase" of the assault, more than 100 missiles were launched from land and sea, primarily short-range ballistic missiles, but also those of medium-range, cruise missiles, and surface-to-air missiles.

The main targets were barracks, ammunition warehouses, and airfields, before ground forces moved in.

Ukraine reported columns of troops penetrated its borders into Chernihiv, Kharkiv, and Luhansk in the east - and also landed by sea at the cities of Odessa and Mariupol in the south.

However, Ukrainian forces have reportedly halted Russia's advance towards Chernihiv, with fighting restricted to the outskirts of the city.

British intelligence suggests that after a day of "fierce resistance" by Ukrainian troops, it is considered "unlikely" that Russia has achieved its planned objectives for the opening 24 hours of the invasion.

Russia hit with sanctions amid international condemnation

Boris Johnson has hit Russia with what he called the "largest set of sanctions ever imposed anywhere by the UK government" - targeting individuals including Mr Putin's former son-in-law.

Making a statement in the Commons, the prime minister said that more than 100 businesses and individuals will be tackled in total, including "all the major manufacturers that support Putin's war machine".

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EU leaders also agreed to another set of sanctions, taking aim at Russia's financial, transport and energy sectors.

Ursula von der Leyen, president of the European Commission, said they included targeting 70% of the Russian banking market and key state-owned companies.

French President Emmanuel Macron, who held a "frank, direct, quick" call with Mr Putin following the invasion, said separate sanctions would be forthcoming from Paris.

And Joe Biden said "strong limitations" will be imposed on what can be exported from the US to Russia.

However, the US president insisted that US troops "will not be engaged in the conflict with Russia in Ukraine", with soldiers instead deployed to eastern European NATO allies to "reassure" them.

Thousands attend protests in Russia and beyond

More than 1,700 anti-war protesters have been arrested across 54 cities in Russia - as scores of demonstrators voice their fury over the invasion of Ukraine.

Protests have also been held across Europe, including in Spain, France, Switzerland, Hungary, and Poland.

In the UK, hundreds sung the Ukrainian national anthem outside Downing Street in central London - and crowds held Ukrainian flags aloft and chanted "Glory to Ukraine" outside the Russian consulate in Edinburgh.

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